BoilerFaultCodesTechnical description
Excessive burner noise, rumbling noises
What causes this fault?
This issue occurs when debris like magnetite or limescale builds up inside the main heat exchanger, narrowing the channels where water flows. Because the water cannot circulate freely, it begins to boil rapidly and turn into steam bubbles, which creates the loud rumbling or 'kettling' noises you are hearing. Over time, this restricted flow puts extra strain on the pump and reduces the efficiency of your heating.
This problem often becomes more noticeable in autumn and winter when the boiler is under high demand and the burner stays on for longer periods.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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